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Debra P. Coffin - One of the best experts on this subject based on the ideXlab platform.
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geographic patterns of simulated establishment of two Bouteloua species implications for distributions of dominants and ecotones
Journal of Vegetation Science, 1999Co-Authors: Tamera J Minnick, Debra P. CoffinAbstract:. Our overall objective was to use a soil water model to predict spatial patterns in germination and establishment of two important perennial C4-bunchgrasses across the North American shortgrass steppe and desert grassland regions. We also predicted changes in establishment patterns under climate change scenarios. Bouteloua gracilis dominates the shortgrass steppe from northeastern Colorado to southeastern New Mexico. Bouteloua eriopoda dominates desert grasslands in central and southern New Mexico. Germination and establishment for each species were predicted at 16 sites along the gradient using a daily time step, multi-layer soil water model (SOILWAT) to determine the percentage of years that temperature and soil water criteria for germination and establishment were met. Percentage of years with predicted establishment decreased from north to south for B. gracilis, but increased from north to south for B. eriopoda, comparable to observed dominance patterns. The 95 % confidence interval around the point at which simulated establishment were equal for the two species was near the location of the shortgrass steppe-desert grassland ecotone where both species are abundant. The intersection in percentage of years with establishment for the two species was predicted to move further north when climate was scaled using three Global Circulation Models (GCMs), indicating a possible northward expansion of B. eriopoda. Our results suggest that recruitment by seed may be an important process in determining, at least in part, the geographic distribution of these two species. Changes in climate that affect establishment constraints could result in shifts of species dominance that may or may not be accompanied by changes in species composition.
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The Importance of Soil Water in the Recruitment of Bouteloua Gracilis in the Shortgrass Steppe
Ecological Applications, 1994Co-Authors: William K. Lauenroth, Osvaldo E Sala, Debra P. Coffin, T.b. KirchnerAbstract:In the shortgrass steppe region of North America there is a controversy about the ability of the dominant species to recruit from seedlings. The prevailing view is that Bouteloua gracilis is incapable of recruitment from seedlings in areas receiving
Wolfgang Pittroff - One of the best experts on this subject based on the ideXlab platform.
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Degradación in vitro de Bouteloua repens por cultivos de R. flavefaciens y F. succinogenes aislados de ganado alimentado con pastos tropicales en Colombia
Corpoica Ciencia y Tecnología Agropecuaria, 2003Co-Authors: Faisury Ossa, Martha Liliana Arcos, Tito Efraín Díaz, Wolfgang PittroffAbstract:The capacity to degrade the cellular wall of Bouteloua repens of 12 isolates of Ruminococcus flavefaciens and 17 isolates of Fibrobacter succinogenes was determined. A procedure was developed to standardize both, the inoculum and the substrate concentration for in vitro incubations of pure culture isolates.The ruminal bacteria were isolated from either Bos indicus cattle from the Alto Magdalena region of Colombia, grazing Bouteloua repens, and Sanmartinero cows (a Colombian criollo breed) from the eastern lowlands (Llanos Orientales) of Colombia, grazing Brachiara spp. The isolates identity was confirmed using molecular methods. All isolates of F. succinogenes showed a high capacity to degrade cell wall preparations of Bouteloua repens, than those of R. flavefaciens (P
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degradacion in vitro de Bouteloua repens por cultivos de r flavefaciens y f succinogenes aislados de ganado alimentado con pastos tropicales en colombia
Corpoica Ciencia y Tecnología Agropecuaria, 2003Co-Authors: Faisury Ossa, Martha Liliana Arcos, Tito Efraín Díaz, Wolfgang PittroffAbstract:The capacity to degrade the cellular wall of Bouteloua repens of 12 isolates of Ruminococcus flavefaciens and 17 isolates of Fibrobacter succinogenes was determined. A procedure was developed to standardize both, the inoculum and the substrate concentration for in vitro incubations of pure culture isolates.The ruminal bacteria were isolated from either Bos indicus cattle from the Alto Magdalena region of Colombia, grazing Bouteloua repens, and Sanmartinero cows (a Colombian criollo breed) from the eastern lowlands (Llanos Orientales) of Colombia, grazing Brachiara spp. The isolates identity was confirmed using molecular methods. All isolates of F. succinogenes showed a high capacity to degrade cell wall preparations of Bouteloua repens, than those of R. flavefaciens (P<0.0001).The effect of individual isolated on cell wall digestibility was also highly significant (P<0.0001). Native isolates surpassed considerably the reference strains of R. flavefaciens ATCC 19208 (12.83% vs. 6.83%) and F. succinogenes ATCC 19169 (13.77% vs. 7.94%) on their capacity to digest Bouteloua repens cellular wall.This difference was highly significant (p<0.05) for all isolates. Findings suggest that in tropical conditions native ruminal bacteria has developed a high capacity to degrade lignocellulose. Further research about the potential usefulness of specific inocula or enzyme extracts developed from such isolates in improving the degradability of low quality forages by cattle or what industrial applications can be improved by the use of these products.
María Elena Siqueiros-delgado - One of the best experts on this subject based on the ideXlab platform.
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Hidden in plain sight: Morphological and phylogenetic evidence for Bouteloua arizonica, a new species distinct from Bouteloua aristidoides (Poaceae, Chloridoideae)
Plant Diversity, 2020Co-Authors: Luis Fernando Cuellar-garrido, María Elena Siqueiros-delgadoAbstract:Abstract Two varieties of Bouteloua aristidoides have been recognized, the widespread var. aristidoides and the more narrowly distributed var. arizonica. The two varieties differ in inflorescence form even more than that seen between many other closely related species of Bouteloua. We therefore asked whether these taxa might be better regarded as distinct species. A total of 93 vouchers were studied by using morphometry (principal components analysis and statistical tests), leaf micromorphology, ancestral state reconstruction, and/or molecular (ITS, trnC-rpoB and trnT-L-F) phylogenetic analyses. Except from the ITS tree, all results supported elevation of Bouteloua aristidoides var. arizonica to the rank of species, thus the new combination Bouteloua arizonica (M.E. Jones) L.F. Cuellar & Columbus comb. nov. et stat. nov., is proposed. Chloroplast and combined chloroplast-nuclear molecular trees depicted var. arizonica as monophyletic (even in sympatric populations with var. aristidoides) and reveals phylogenetic structure within var. aristidoides for which the presence of new undescribed varieties of Bouteloua aristidoides (different from Bouteloua arizonica) is addressed. Bouteloua arizonica differs from Bouteloua aristidoides in having fewer branches per inflorescence, a bigger branch with more spikelets, and a shorter branch extension. Scanning electron microscopy revealed the presence of papillae on leaves of Bouteloua arizonica as a clear synapomorphy. Growing mature plants of Bouteloua arizonica from seeds in a greenhouse revealed a strong cleistogamous nature for this species for which gene flow in sympatric populations with Bouteloua aristidoides seems unlikely. A taxonomic treatment and distribution map for identification of Bouteloua arizonica is provided.
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Rediscovery of Bouteloua vaneedenii (Gramineae: Chloridoideae): endemic species from the West Indies
Revista Mexicana De Biodiversidad, 2011Co-Authors: María Elena Siqueiros-delgado, Ramona Oviedo-prieto, Rosa Cerros-tlatilpa, Rafael Del Risco-villalobos, Iralis Ventosa-rodríguezAbstract:Bouteloua vaneedenii is an endemic and extremely rare grass of the West Indies. Very few collections are known, and the most recent collection is from 1922. With the aim of finding the species, a team of Mexican and Cuban agrostologists conducted a field trip and found B. vaneedenii in the same locality where it was collected in 1922 on dry limestone rocks. Although it was stated that B. vaneedenii probably was extinct from Cuba, vigorous populations remain in at least 2 localities in Pastelillo. Further exploration may lead to the discovery of additional populations and the reevaluation of its current conservation status.
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Rediscovery of Bouteloua vaneedenii (Gramineae: Chloridoideae): endemic species from the West Indies Redescubrimiento de Bouteloua vaneedenii (Gramineae: Chloridoideae): especie endémica de las Indias Occidentales
2011Co-Authors: María Elena Siqueiros-delgado, Ramona Oviedo-prieto, Rosa Cerros-tlatilpa, Rafael Del RiscoAbstract:Bouteloua vaneedenii is an endemic and extremely rare grass of the West Indies. Very few collections are known, and the most recent collection is from 1922. With the aim of finding the species, a team of Mexican and Cuban agrostologists conducted a field trip and found B. vaneedenii in the same locality where it was collected in 1922 on dry limestone rocks. Although it was stated that B. vaneedenii probably was extinct from Cuba, vigorous populations remain in at least 2 localities in Pastelillo. Further exploration may lead to the discovery of additional populations and the reevaluation of its current conservation status.
Yair Manuel - One of the best experts on this subject based on the ideXlab platform.
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caracterizacion bromatologica de tres especies de gramineas aristida curvifolia Bouteloua gracilis y b uniflora
2019Co-Authors: Pacheco Cruz, Yair ManuelAbstract:Determinar el valor nutritivo de las especies Bouteloua gracilis, Bouteloua uniflora y Aristida curvifolia, en el Rancho Ganadero Experimental Los Angeles
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caracterizacion bromatologica de tres especies de gramineas aristida curvifolia Bouteloua gracilis y b uniflora
2019Co-Authors: Pacheco Cruz, Yair ManuelAbstract:La produccion forrajera en los pastizales naturales del norte de Mexico para la ganaderia de bovinos es una actividad importante debido a que es la fuente principal de alimentacion para la nutricion de ganado vacuno. Se realizo el analisis bromatologico de tres especies de zacate forrajeros: Bouteloua gracilis, Bouteloua uniflora y Aristida curvifolia. En junio de 2018 se tomaron 24 muestras de forraje al azar en el Rancho Ganadero Los Angeles, al sureste de Coahuila, en las pastas 6, 7 y 8 donde la vegetacion es pastizal mediano abierto, matorral desertico microfilo e izotal. En el laboratorio las muestras de forraje se pesaron y secaron en una estufa a 60° durante 48 horas Se determino el porcentaje de proteina cruda, extracto etereo, fibra cruda, extracto libre de nitrogeno, total de nutrientes digestibles y cenizas. Los datos se analizaron con la prueba de Tukey. En la mayor concentracion de proteina cruda (4.1 %) se encontraron diferencias significativas (P<0.05) en la especie Bouteloua gracilis. La especie Aristida curvifolia presento el mayor porcentaje en fibra cruda (52.66 %). La especie Bouteloua uniflora no presento diferencias significativas respecto a Bouteloua gracilis y Aristida curvifolia en el contenido de cenizas, extracto etereo, fibra cruda, extracto libre de nitrogeno y total de nutrientes digestibles. Las especies forrajeras tanto como gramineas y Aristidas son importante en la nutricion del animal por ser una fuente de alimentacion a bajo costo, ademas de su aporte nutricional para el crecimiento y mantenimiento del ganado
Faisury Ossa - One of the best experts on this subject based on the ideXlab platform.
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Degradación in vitro de Bouteloua repens por cultivos de R. flavefaciens y F. succinogenes aislados de ganado alimentado con pastos tropicales en Colombia
Corpoica Ciencia y Tecnología Agropecuaria, 2003Co-Authors: Faisury Ossa, Martha Liliana Arcos, Tito Efraín Díaz, Wolfgang PittroffAbstract:The capacity to degrade the cellular wall of Bouteloua repens of 12 isolates of Ruminococcus flavefaciens and 17 isolates of Fibrobacter succinogenes was determined. A procedure was developed to standardize both, the inoculum and the substrate concentration for in vitro incubations of pure culture isolates.The ruminal bacteria were isolated from either Bos indicus cattle from the Alto Magdalena region of Colombia, grazing Bouteloua repens, and Sanmartinero cows (a Colombian criollo breed) from the eastern lowlands (Llanos Orientales) of Colombia, grazing Brachiara spp. The isolates identity was confirmed using molecular methods. All isolates of F. succinogenes showed a high capacity to degrade cell wall preparations of Bouteloua repens, than those of R. flavefaciens (P
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degradacion in vitro de Bouteloua repens por cultivos de r flavefaciens y f succinogenes aislados de ganado alimentado con pastos tropicales en colombia
Corpoica Ciencia y Tecnología Agropecuaria, 2003Co-Authors: Faisury Ossa, Martha Liliana Arcos, Tito Efraín Díaz, Wolfgang PittroffAbstract:The capacity to degrade the cellular wall of Bouteloua repens of 12 isolates of Ruminococcus flavefaciens and 17 isolates of Fibrobacter succinogenes was determined. A procedure was developed to standardize both, the inoculum and the substrate concentration for in vitro incubations of pure culture isolates.The ruminal bacteria were isolated from either Bos indicus cattle from the Alto Magdalena region of Colombia, grazing Bouteloua repens, and Sanmartinero cows (a Colombian criollo breed) from the eastern lowlands (Llanos Orientales) of Colombia, grazing Brachiara spp. The isolates identity was confirmed using molecular methods. All isolates of F. succinogenes showed a high capacity to degrade cell wall preparations of Bouteloua repens, than those of R. flavefaciens (P<0.0001).The effect of individual isolated on cell wall digestibility was also highly significant (P<0.0001). Native isolates surpassed considerably the reference strains of R. flavefaciens ATCC 19208 (12.83% vs. 6.83%) and F. succinogenes ATCC 19169 (13.77% vs. 7.94%) on their capacity to digest Bouteloua repens cellular wall.This difference was highly significant (p<0.05) for all isolates. Findings suggest that in tropical conditions native ruminal bacteria has developed a high capacity to degrade lignocellulose. Further research about the potential usefulness of specific inocula or enzyme extracts developed from such isolates in improving the degradability of low quality forages by cattle or what industrial applications can be improved by the use of these products.